Finally got started playing with PICs using a neat little protoboard
from the UK, an ITU PIC-1 burner, 16F84s and a PicBASIC compiler.

Having great fun with Leds and switches and such. Just added an ADC0831
for 8-bit A/D, and tried the SEROUT function to display voltage values
on a PC. Therein lies the rub.

I realize that the 0 to +5v swing from the PIC is not RS-232 standard. I
found that the trusty desktop PC reads it just fine (both from Windows95
and DOS), but neither of the laptops I tried will work.

Am I correct in the belief that the laptop problem is related to the use
of CMOS circuitry for the serial ports?

If that be true, the obvious solution would be to add a level shifter
such as a MAX233 to the PIC protoboard. Any other suggestions for quick
and dirty level shifting?

jim nestor
nestoji@home.com